Process of treating textile fabrics



Dec. 31, 1935. s. H. RHODES I Y PROCESS OF TREATING TEXTILEFABRIQS Filed April 24. 1934 ATTORNEYS.

Patented Dec. 31, 1935 ment of the same goods by my herein disclosed 2,026,190 "PRooEss F TREATING TEXTILE FABRICS George Henry Rhodes, Fallltiver, Application April 24, 1934, Serial No. 722,067

2 Claims. (01. 91-68) This invention relates to the process of treating textile fabrics, and has for one of its objects the preserving of fabrics against outdoor exposure, such asexposure to the sun and rain.

Grey goods which are used out of doors for a period of six months, particularly the summer months, lose approximately fifty per cent of their original tensile strength, and by the treatprocess, the same exposure will cause them to lose only ten tofifteen per cent of their original tensile strength, thus a further object of the invention is to greatly enhance the strength of the cloth.

A further object of my invention is to treat this fabric in a continuous process by continuously moving the web of fabric so'that it is caused to contact with the different solutions by which an insoluble salt is formed on the fibres to preserve and protect them.

With these and other objects in view, the invention consists of certain novel features of construction, as will be more fully described, and

particularly pointed out in the appended claims.

In the accompanying drawing:

Fig. 1 is a side elevation partly in section large- 1y diagrammatic showing the passage. of a web of cloth through my apparatus;

Fig. 2 is a similar view of a slightly different apparatus using a different preservative on the fabric and requiring a slightly diiferent'arrangement for the accommodation thereof.

This process is particularly adapted for use on what is known as tobacco cloth of a construction consisting of from twenty warps by twelve fillings to twenty-eight warps by twenty-four fillings per inch, and although this process has been found of advantage in this tobaccocloth, it is by no means restricted to. the use on cloth of. this particular construction.

In this process the grey goods are drawn from a suitable package, not shown, usually in pairs at the rate of from fifteen to thirty yards per minute, the different webs being illustrated at H] and It in the accompanying drawing, where they are caused to contact with a bath IQ of hot water at from 90 to 100 centigrade, these goods are conveyed into the bath over a'guide roll l3 and out again through the squeezer'olls l4 and I5 which may be adjusted as at I 6 to administer the desired pressure for squeezing out the liquid through which the webs have just passed. The purpose of this hot water treatment is to remove the sizing in the cloth, and to better effect this removal, a penetrating agent, such as N ekal .acetate liquor l8.

BX, a'preparation marketed by the General Dye Stuffs Corporation, may be used to better or to hasten the removal of the sizing fromthe grey goods.

The goods are then conveyed into an adjacent 5 tank; I] containing asolution l8 of lead acetate (12% to 14%), which solution is maintained at I. substantially 50 to 60 oentigrade, the solution being acidified to the extent of 0.1% with acetic acid or formic acid. In order tomaintaintlre goods in the bath for the required length of time during their continuous passage so that this lead acetate solution may penetrate the goods, the

goods are passed about rolls l9 and in a sumcient number to maintain the web in the bath 5 the required length of time depending uponthe character of the goods. I-have here shown the goods as being given 16 ends or 16 stretches be-.

tween rolls in the solution causing it to remain therein about one minute. As the goods emerge 20 from the tank, they pass through squeeze rolls 2| and 22 adjusted at 23 to provide the proper pressure to force the lead acetate into the fibres and squeeze back into the tank the excess portions of lead acetate which are not absorbed by the fibres.

As this solution I will be gradually taken up by the cloth passing through it I have provided a supply tank 24 having a conduit 25 to replen- I ish the lead acetate solution as it is taken up by the cloth. This is controlled by a valve 26 and should the supply be greater than taken up by the cloth, there-will bean outlet for the solution by an overflow. conduit 21.

The goods are' then conveyed to tank 28 containing a solution 29 of sodium dichromate where the webs enter over a guide roll 30 and are given a required number of ends, here shown as IS in the solution by passage over rolls 3| at the bottom and 32 at the top, during its travel through this solution. The sodium dichromate reacts with the lead acetate on the fibres of the cloth to provide insoluble lead chromate as a coating on the fibres of the fabric, and as the cloth leaves the bath 29, pressure is applied through the squeeze rolls 33 and 34 adjusted-as at 35 to remove the excess liquor and allow it to drain back into the tank. The liquor in this sodium dichromate bath is maintained at, from to 60 centigrade, the same as the temperature of the lead 50 The cloth is in this bath about one minute or substantially the same as in bath I8.

The chromate bath, also, is depleted in strength as the chromate is taken on by the goods andas ture of desired 5% sodium chromate when desired.

After emerging from the chromate solution, the webs are then passed about guide rolls 4| at the bottom and ,42 at the top, a sufficient number :of stretches to permit spraying by nozzles 42 and through washing with water which effects a thorough cleaning of the cloth and a removal of any of the excess lead chromate which has not become fixed on the fibres. These goods are then passed through another set of squeeze rolls 43 and 44 adjusted as at 45 and then passed into tank 46 containing a solution 41 of starch or dextrine (2% to 6%) maintained at from to 60 centigrade, where it is given a sufiicient number of ends about the lower rolls 48 and upper rolls 49, and it then emerges through squeeze rolls 50 and 5| adjusted as at 52, after which it is suitably dried and then folded into suitable containers 53 and 54 by the swinging arms 51 being separated by the rolls 55 and 56, or thesewebs may be otherwise packaged for the desired purposes, the cloth now being ready for tentering with further drying for sizing as to width. This starch solution may also be replenished by tank 58 and conduit 59 controlled by valves 66, as above pointed out.

While I have described the above process as usinglead acetate, I have selected this material as it is at present the least expensive in the market, for providing a soluble lead compound, other lead compounds might be used, such as a nitrate, for example, if preferred, and similarly in order to provide the chromate radical, I have selected sodium chromate as the least expensive at this time, but any soluble chromate such as potassium or other chromate solution may be used that this chromate radical may be provided for chemically reacting and combining with the lead of the lead acetate, nitrate or the like.

Alternatively, instead of providing lead chromate on the cloth, I-may provide iron oxide, and in Figure 2 I have illustrated this alternative method, which is similar to that above described with the exception that I provide a drying operation at one point and a soaping operation at another point in connection with this alternative method. The'solution used in place of. the solution I8 is designated as 60 and consists of nitrate of iron at 20 centigrate, and 6.5 Twad.

In this case, I will perform a drying operation at 6| over suitable heated drums 62 before passing the fabric into the second solution 63 which will consist of a 2% solution of soda ash, at 60 centigrade, the chemicalreaction taking place is to form ferric oxide on the fibres which is insoluble in water.

The fabric is washed, as heretofore explained and the second added step in this alternative process is to provide a tank 64 containing 2% soap solution 65 in which the material is given a suflicient number of ends over guide rolls 66 5 at the bottom, and 61 at the top, and then passed outwardly through squeeze rolls 68 and 69 adjusted at 16 and then into the starch ordextrine solution, as above explained. A reservoir of supply liquid II with conduit 12 and control 13 is also provided for this soap solution.

The apparatus which I have described is all mounted upon a suitable cement floor graded for drainage so that any solution that'is let out of any of the tanks will suitably reach the drain and a sort of platform or walk is arranged about. the tanks for convenience of movement about them by the operators, the washing. by sprays thus drawing down onto this graded floor where it is conveyed to the drainage.

Although I have described and prefer to use a boiling of the cloth previous to contacting it with the chemical preserving solutions, in some cases it is unnecessary to boil or bleach or treat to remove the sizing of the grey goods. This formation of either lead chromate or iron oxide is performed by this method quickly andrapidly and in acontinuous process of passing the grey goods in open web form through the apparatus; and bythe arrangement of the replenishing solutions, the concentrations of the original solutions may be maintained. The concentrations are maintainedapproximately as above stated; however, the greater the concentration of the lead chromate on the fibres, the greater amount of protectiveness will be afiorded the cloth against exposure to rain and sun, and thus as these elements cannot so readily attack the fibres coated, as above described, the tensile strength of the cloth is maintained over a greater length of 40 time. The starch serves also to protect the lead chromate coating and as a finish for the goods.

The foregoing description is directed towards the method and construction illustrated, but I desire it tobe understood that I reserve the privi- 5 lege of restorting to all the equivalent changes to which the construction and method are susceptible, the invention being defined and limited onl by the terms of the appended claims.

I claim:

1. The process of treating a fabric to preserve the tensile strength of the same which consists in continuously contacting a web of fabric with an -acidulated solution of lead acetate for a sufllcient length of time for penetration, and then 55 continuously contacting the web with a solution of sodium dichromate to form lead chromate on the fibres of the fabric.

2. The process of treating a fabric to preserve the same which consists in continuously passing 60 a web of fabric through a bath of an acidulated solution of lead acetate for a sufi'icient length of time for penetration, and then passing the web through a solution of sodium dichromate to form lead chormate on the fibres of the fabric.

GEORGE HENRY RHODES. 

